Motor driven appliance

A motor driven appliance comprising:

• a light source;
• a lighting unit configured to turn on the light source;
• a motor configured to generate a driving force for work to be done by a user of the motor driven appliance;
• an operation unit configured to be operated by the user to actuate the motor;
• an operation detector configured to detect that the operation unit is operated, and to output an operation detection signal that indicates that the operation unit is operated;
• a reference signal output unit configured to output at least one reference signal that can be used as a reference for determining whether the detection by the operation detector is normal;
• a determination unit configured to determine whether the operation unit is actually operated based on the operation detection signal and the at least one reference signal;
• and
• a control unit configured to control operation of the lighting unit based on the determination made by the determination unit,
• wherein the operation detector comprises at least one first terminal for outputting the operation detection signal, and at least two second terminals distinct from the at least one first terminal,
• wherein the reference signal output unit is further configured to output as the at least one reference signal a signal that indicates whether a short circuit is occurring between the at least two second terminals.

A motor driven appliance comprising:

• a light source;
• a lighting unit configured to turn on the light source;
• a motor configured to generate a driving force for work to be done by a user of the motor driven appliance;
• an operation unit configured to be operated by the user to actuate the motor;
• an operation detector configured to detect that the operation unit is operated, and to output an operation detection signal that indicates that the operation unit is operated;
• a reference signal output unit configured to output at least one reference signal that can be used as a reference for determining whether the detection by the operation detector is normal;
• a determination unit configured to determine whether the operation unit is actually operated based on the operation detection signal and the at least one reference signal;
• and
• a control unit configured to control operation of the lighting unit based on the determination made by the determination unit,
• wherein the operation unit comprises a first contact connected to the power source configured to supply to the motor an electric power to drive the motor, and a second contact connected to the motor, the operation unit being configured to electrically connect the first contact and the second contact to one another when the operation unit is operated, and
• the reference signal output unit is further configured to output as the at least one reference signal at least one signal that indicates at least one kind of physical quantity related to an impedance between the first contact and the second contact.